Acoustic tone equalizer



June 23, 1959 R. P. MERCURIUS 7 2,891,629

ACOUSTIC TONE EQUALIZER Filed Dec. 9, 1957 3 Sheets-Sheet 1 INVENTOR.

R. P. MERCURIUS 2,891,629

ACOUSTIC TONE EQUALIZER 3 Sheets-Sheet 2 June 23, 1959 Filed Dec. 9, 1957 June 23, 1959 R. P. MERCURIUS ACOUSTIC TONE EQUALIZER 3 Sheets-Sheet 3,

Filed D90. 9, 1957 United States Patent 2,891,629 ACOUSTIC TONE EQUALIZER Randolph P. Mercurlus, Bronx, N.Y.

Application December 9, 1957, Serial No. 701,425

Claims. (Cl. 181-31) This invention relates to audio equipment and more particularly to a sound amplifier.

More specifically, this invention relates to sound amplifiers of the type disclosed in my Patent No. 2,277,525, granted March 24, 1942, and has as one of its objects the provision of an acoustic tone equalizer which can adequately handle a capacity volume of sound emanating from a low frequency range speaker and a mid range frequency speaker.

Another object of the present invention is to provide a sound amplifier which includes a single housing for enclosing the various speakers and bafile devices in a compact and efiicient arrangement.

Still another object of the present invention is to provide novel baffle means which defines a passageway that communicates with both the low frequency and mid frequency ranges speaker compartments so as to simultaneously amplify sound emanating therefrom and for directing the equalized sound waves outwardly through a single main port.

All of the foregoing and still further objects and advantages of this invention will become apparent from a study of the following specification, taken in connection with the accompanying drawing, wherein:

Figure l is a perspective view of an enclosure embodying the present invention;

Figure 2 is a transverse cross sectional view taken along line 2--2 of Figure 3;

Figure 3 is a transverse cross sectional view taken along line 3--3 of Figure 2;

Figure 4 is a transverse cross sectional view taken along line 4--4 of Figure 3;

Figure 5 is an enlarged perspective view, with parts broken away, of the device shown in Figure 1;

Figure 6 is a transverse cross sectional view taken along line 6-6 of Figure 2;

Figure 7 is a fragmentary cross sectional view taken along line 7-7 of Figure 2; and

Figure 8 is a fragmentary perspective view of certain parts of the apparatus shown in Figure 5.

Referring now to the drawing, and more particularly to Figures 1 to 5 thereof, an enclosure 10 made in accordance with the present invention is shown to include a rectangular housing defined by side walls 12 and a back wall 11. A first partition 13 divides the compartment defined by the side walls 12 into an outer compartment and an inner compartment. A main mounting panel 15 is supported in spaced parallel relationship in front of the first partition 13 and has a circular cutout 16 for mounting a low frequency range speaker 17 and a smaller circular cutout 21 for mounting a mid range frequency speaker 20. A vertical divider 18 separates the low range speaker compartment 19 from the mid range speaker compartment 23. The mounting panel 15 is also provided with relief ports 22 and a symmetrical irregular shaped main port 24.

A horizontal wall 25 separates the mid range speaker 2,891,629 Patented June 23, 1959 compartment '23 from the tone chamber 26. A rectangular bafiile 28 supported by means of a medial divider 29 from the transverse horizontal wall 25 defines a continuous passageway of uniform cross sectional area 32 which extends completely around the bafile 28. Perforations 34 in the horizontal wall 25 provide communication between the mid range frequency chamber 23 and the bafiie defined passageway 26 which is also in communication with the interior of the baffle 28 by means of similar perforations 31 at the top of the baffle and at one side of the medial divider 29 opposite from the per-- forations 34 in the horizontal wall 25. The sound waves entering the interior of the baffle 28 are then directed outwardly through the main port 24, as will be hereinafter described.

A low range frequency baflle 40 having one portion in the form of a parallelogram defined by an upper wall 41, a spaced parallel lower wall 42, an inclined side 45, and a vertical side 48, is disposed directly behind an owal opening 37 in the main divider wall 13 which provides communication with the interior of the low frequency range speaker compartment 19. The upper wall 41 of this parallelogram shaped baffle portion is provided with an opening 43 which communicates with a passageway 46 defined by the inclined side wall 45 and another extended inclined wall member 51. The extended inclined wall 51 defines with the upper side wall 12 of the enclosure a passageway which increases in volume as it approaches the side of the enclosure containing the mid range frequency speaker compartment 23. A port 54 in the main divider wall 13 provides communication with this enlarged portion of the passageway and the interior of the mid range frequency compartment 23.

It will now be recognized that sound waves emanating from the low range speaker 17 will pass directly into the mid range compartment 23 to mix with the sound Waves emanating from the mid range speaker 20. These sound waves equalize each other and pass through the perforations 34 in the horizontal wall 25 into the tone chamber, from which they are directed outwardly through the main port 24 in the manner hereinbefore described. A grill cloth 57 covers the front of the enclosure, as shown in Figure 1, and suitable braces 56 are used to rigidity the unit to reduce the transmission of vibration from one baifie or from one panel to another.

Since the sound waves of all of the speakers of the enclosure are directed through a single tone chamber, such has the effect of equalizing the tone of all of the speakers, whereby the sound produced thereby is directed outwardly through a single main port. Thus, a very efficient and compact acoustic tone equalizer enclosure has been provided which can be used for a wide variety of purposes in any audio system.

While this invention has been described with particular reference to the construction shown in the drawing, it is to be understood that such is not to be construed as imparting limitations upon the invention, which is best defined by the claims appended hereto.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. An acoustic tone equalizer comprising, in combination, a rectangular outer housing, first partition means dividing the space within said outer housing into inner and outer compartments, second partition means dividing said outer compartment into a low range frequency speaker chamber and a mid range frequency speaker chamber, a speaker mounting panel spaced in front of and parallel to said divider wall, said speaker mounting panel having a main port therein, bafile means associated with both of said speaker chambers for directing sound waves out of said main port, said first partition means comprising a divider wall having ports communicating with both of said speaker chambers, said speaker mounting panel also having portions defining apertures, speakers in communication with said apertures carried by said aperture defining portions, and said second partition means comprising a panel extending normal to and between said divider wall and said mounting panel.

2. An acoustic tone equalizer as set forth in claim 1, comprising a horizontal wall extending beneath said mid range speaker chamber defining a tone chamber therebeneath, said main port being a symmetrical irregularly shaped opening in said mounting panel directly in front of said tone chamber.

3. An acoustic tone equalizer as set forth in claim 2, wherein said bafile means comprises an enclosure directly behind the port in said divider wall communicating with said low range speaker chamber, and said References Cited in the file of this patent FOREIGN PATENTS 930,958 France Sept. 8, 1947 

